New York cop Frank Keller (Al Pacino) is divorced, disenchanted and coming close to retirement. A serial killer strikes in the city, attacking men in their bedrooms and it would seem that a woman using the personal ads is responsible. Keller teams up with fellow cop Sherman (John Goodman), who has also had a serial killer operating on his patch, and together they dream up the idea of placing their own advertisements in the personal columns, dating the women and collecting their fingerprints. One woman who answers the ad is the beautiful and seductive Helen (Ellen Barkin). Frank falls heavily for her and against his better judgement begins an affair with the prime suspect.